//The contents of this file are subject to the Mozilla Public License Version 1.1
//(the "License"); you may not use this file except in compliance with the 
//License. You may obtain a copy of the License at http://www.mozilla.org/MPL/
//
//Software distributed under the License is distributed on an "AS IS" basis,
//WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
//for the specific language governing rights and
//limitations under the License.
//
//The Original Code is "The Columba Project"
//
//The Initial Developers of the Original Code are Frederik Dietz and Timo Stich.
//Portions created by Frederik Dietz and Timo Stich are Copyright (C) 2003. 
//
//All Rights Reserved.
package org.columba.mail.folder.mh;

import java.io.File;
import java.io.FileFilter;
import java.util.regex.Matcher;
import java.util.regex.Pattern;


/**
 * @author timo
 *
 * To change this generated comment edit the template variable "typecomment":
 * Window>Preferences>Java>Templates.
 * To enable and disable the creation of type comments go to
 * Window>Preferences>Java>Code Generation.
 */
public class MHMessageFileFilter implements FileFilter {
    private static final Pattern filePattern = Pattern.compile("[0-9]+");
    protected static MHMessageFileFilter myInstance;
    private Matcher matcher;

    protected MHMessageFileFilter() {
        matcher = filePattern.matcher("");
    }

    public static MHMessageFileFilter getInstance() {
        if (myInstance == null) {
            myInstance = new MHMessageFileFilter();
        }

        return myInstance;
    }

    /**
 * @see java.io.FileFilter#accept(java.io.File)
 */
    public boolean accept(File arg0) {
        matcher.reset(arg0.getName());

        return (arg0.isFile()) && matcher.matches();
    }
}
